1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2 3 #include <linux/iio/iio.h> 4 #include <linux/mod_devicetable.h> 5 #include <linux/module.h> 6 #include <linux/regmap.h> 7 #include <linux/spi/spi.h> 8 9 #include "bmi270.h" 10 11 /* 12 * The following two functions are taken from the BMI323 spi driver code. 13 * In section 6.4 of the BMI270 data it specifies that after a read 14 * operation the first data byte from the device is a dummy byte 15 */ 16 static int bmi270_regmap_spi_read(void *spi, const void *reg_buf, 17 size_t reg_size, void *val_buf, 18 size_t val_size) 19 { 20 return spi_write_then_read(spi, reg_buf, reg_size, val_buf, val_size); 21 } 22 23 static int bmi270_regmap_spi_write(void *spi, const void *data, 24 size_t count) 25 { 26 u8 *data_buff = (u8 *)data; 27 28 /* 29 * Remove the extra pad byte since its only needed for the read 30 * operation 31 */ 32 data_buff[1] = data_buff[0]; 33 return spi_write_then_read(spi, data_buff + 1, count - 1, NULL, 0); 34 } 35 36 static const struct regmap_bus bmi270_regmap_bus = { 37 .read = bmi270_regmap_spi_read, 38 .write = bmi270_regmap_spi_write, 39 }; 40 41 static const struct regmap_config bmi270_spi_regmap_config = { 42 .reg_bits = 8, 43 .val_bits = 8, 44 .pad_bits = 8, 45 .read_flag_mask = BIT(7), 46 }; 47 48 static int bmi270_spi_probe(struct spi_device *spi) 49 { 50 struct regmap *regmap; 51 struct device *dev = &spi->dev; 52 const struct bmi270_chip_info *chip_info; 53 54 chip_info = spi_get_device_match_data(spi); 55 if (!chip_info) 56 return -ENODEV; 57 58 regmap = devm_regmap_init(dev, &bmi270_regmap_bus, dev, 59 &bmi270_spi_regmap_config); 60 if (IS_ERR(regmap)) 61 return dev_err_probe(dev, PTR_ERR(regmap), 62 "Failed to init i2c regmap"); 63 64 return bmi270_core_probe(dev, regmap, chip_info); 65 } 66 67 static const struct spi_device_id bmi270_spi_id[] = { 68 { "bmi260", (kernel_ulong_t)&bmi260_chip_info }, 69 { "bmi270", (kernel_ulong_t)&bmi270_chip_info }, 70 { } 71 }; 72 73 static const struct of_device_id bmi270_of_match[] = { 74 { .compatible = "bosch,bmi260", .data = &bmi260_chip_info }, 75 { .compatible = "bosch,bmi270", .data = &bmi270_chip_info }, 76 { } 77 }; 78 79 static struct spi_driver bmi270_spi_driver = { 80 .driver = { 81 .name = "bmi270", 82 .of_match_table = bmi270_of_match, 83 }, 84 .probe = bmi270_spi_probe, 85 .id_table = bmi270_spi_id, 86 }; 87 module_spi_driver(bmi270_spi_driver); 88 89 MODULE_AUTHOR("Alex Lanzano"); 90 MODULE_DESCRIPTION("BMI270 driver"); 91 MODULE_LICENSE("GPL"); 92 MODULE_IMPORT_NS(IIO_BMI270); 93